The invention relates to an arrangement of a running roller on a coupling journal of a moveable shaft coupling.
In shaft couplings with a conventional arrangement of a running roller, it is essential that the two shafts to be coupled are capable, in relation to one another, of assuming xe2x80x9cbending positionsxe2x80x9d of a static or dynamic type with respect to their axes of rotation and of executing axial movements, without non-uniformities in the rotational speed behaviour occurring on the shafts.
In another arrangement of the running roller as described, for example, in German Published Patent Application No. 28 31 044, the connection of the inner ring of the rolling bearing to the associated ball socket of the ball joint is configured so that the inner ring and ball joint are produced in one piece, while, in order to maintain the additional degree of freedom of the cylindrical coupling journal in relation to the complementary coupling half, the coupling journal is connected to the ball head, associated with it, of the ball joint, so as to be axially displaceable with respect to its geometric major axis, but radially immovably, so that the joint center consequently always coincides with the geometric major axis of the coupling journal. The sliding movements of the coupling journal in relation to the associated ball head, require a costly grinding or honing process in order to produce the relevant sliding faces, without it being possible to avoid completely the excitation of vibrations as a result of frictional resistances or power losses.
In another arrangement of a running roller on a coupling journal of a moveable shaft coupling, as described, for example in European Published Patent Application No. 0 426 186, the above-described disadvantages of the conventional arrangement are to be eliminated in that the inner recess, receiving the ball head, of the inner ring of the rolling bearing, is cylindrical and the ball head fixedly connected to the coupling journal is displaceable in the cylindrical inner recess radially (i.e., in the directions of the bearing axis of the rolling bearing). Thus, in this arrangement, the entire coupling moment introduced into the coupling journal is transmitted to the cylindrical face of the inner ring in a virtually pointing and sliding manner at that point on the ball face which is also exposed to the sliding displacement of the coupling journal in the directions of the bearing axis and therefore to sliding resistance during its relative movements in relation to the complementary coupling half.
It is an object of the present invention to provide an arrangement of a running roller on a coupling journal of a moveable shaft coupling, in which the vibrational excitations in the shafting which originate from frictional resistances between faces which are in sliding contact with one another are reduced.
The above and other beneficial objects of the present invention are achieved by providing an arrangement as described herein.
In one example embodiment of the arrangement of a running roller according to the present invention, both axial sliding movements of the coupling journal in relation to the ball head and axial sliding movements of the ball head in relation to the inner ring are positively prevented, and, furthermore, a fraction of the relative movement necessary for maintaining the additional degree of freedom for the coupling journal in relation to the complementary coupling half is absorbed into the rolling bearing as a rolling movement of the rolling bodies. This arrangement results in a reduction in the sliding fraction of the relative movement and therefore results in a reduction in the vibrational excitation and power losses.
In the arrangement according to the present invention, the coupling journal may be connected, for example, to that joint half of the ball joint which has the concave ball face.
In the arrangement according to the present invention, the need for a separate individual joint part for the ball head may be eliminated.
In another example embodiment of the arrangement according to the present invention, it is possible to insert the ball head of the coupling journal either directly into the central orifice of the inner ring or into the central orifice of a fixing insert and to implement the axial securing of the ball head by one or two fixing inserts.
According to yet another example embodiment of the arrangement according to the present invention, the functions of the rolling-bearing-side joint half of the ball joint and of the axial fixing of said joint half in the directions of the bearing axis of the rolling bearing are integrated into the fixing insert which can be produced in its configuration by a non-fixing hobbing method, so that there is no need for cost-intensive grinding methods and the like in order to produce the joint face, in particular the ball face of this component in the arrangement according to the present invention.
In still another example embodiment of the arrangement according to the present invention, using a fixing insert, the element for configuring the joint portion and the element for fixing the complementary joint half of the coupling journal may be produced in one piece.
In a further example embodiment of the arrangement according to the present invention, using a fixing insert, the fixing insert may be secured, for example, in relation to the inner ring of the rolling bearing, in each case in one directions of the bearing axis, by a collar or by a securing ring.
The rolling bearing may be configured as a loose bearing in order to maintain the additional degree of freedom of the coupling journal for the relative movements of the latter in relation to the complementary coupling half.
The rolling bearing may also be configured with a thrust washer for the rolling bodies.
The number of individual components in the arrangement according to the present invention in the example embodiment that includes thrust washers used for the rolling bodies may be reduced.
The rolling bearing may be configured as a loose bearing for maintaining the additional degree of freedom of the coupling journal for the relative movement of the latter in relation to the complementary coupling half.
In another example embodiment of the arrangement of a running roller on a coupling journal according to the present invention, the formation of a special middle joint portion on a fixing insert is eliminated, and, instead, in each case a simple fixing insert is used for the fixing, in each case in one of the directions of the bearing axis, of the ball head of the coupling journal, the ball head at the same time being inserted directly into the central orifice of the inner ring of the rolling bearing.